Alarm selector apparatus



y 1932. 'L. L. E. CHAUVEAU 1,867,209

ALARM SELFTCTOR APPARATUS Filed May 21, 1929 INVENTOR LOUIS L.E. CHAUVEAU BY 7%MW ATTORNEY Patented July 12, 1932 PATENT OFFICE LOUIS LUGIEN EUGENE CHAUVEAU, OF PARIS, FRANCE ALARM snnncroa APPARATUS Application filed May 21, 1929, Serial No. 364,720, and in France May 22, 1928.

The present application covers two improvements in the apparatus forming the subthere is shown a signal selector device which is adapted to distinguish between a proper redetermined signal and improper signals. ore specifically the device as described in' my copending application is so constructed that upon receipt of a predetermined signal an alarm is actuated. The apparatus for accomplishing this consists of a relay system which measures the time interval of incoming signals, the time interval of spaces and the number of correct signals. If a signal im-.

pulse subject .to certain tolerances is of an improper length or if a space between signals is im roper or if the number of signal interva s is improper the entire mechanism will be returned to its original state.

One of the objects of the present invention is to prevent the selector mechanism from bea ing acted upon by ordinary signals.

Another object of this invention is to simplify the arrangement of the assembly which measures the length of the spaces or intervals between signals.

Another object is to vent the receiving relay which responds continuously to radio signals from hammering on the balance mechanism operating rod.

A further object of this invention is to pro vide means to simplify the space controlling ap aratus.

Sue of the embodiments incorporating these improvements is by way of example described in the following specification when read in connection with theappended drawing in which the single figure represents diaammatically the improvements above re-.

erred to as applied to Figure 1 of my said co ding application.

e- Morse-code signals generally used in radio telegraphy consist of dots having -a len h of an order of one-tenth of one second, an dashes of an order of three-tenths of one second. Now, if these signals are received directly in the receiving relay 54 as provided provide means to prei,

or intervals between signals, the balance for in my said copending application, the arm (wiper) 1 thereof is constantly in' operation and hammers and strikes against the shoulder 2 on the rod 4 adapted to release the balance 49. This is liable to result in mechanical percussions detrimental to the balance system 49. In order to prevent this from happening, in accordance with this invention, an auxiliary relay MN is added to the device which is controlled by the breaker of the radio relay 56. The said auxiliary relay MN in turn controls 54. The relay MN is retarded, for instance, by furnishing it with a copper sheath, in accordance with ordinary practice in telephone work. 'In this waythe relay MN doesnot follow the manual keying because it is retarded by a time interval amounting to around three-tenths of one Second. The result is that solely'dashes lasting over three-tenths of one second are allowed 7 to act upon the balance .49. Evidently, this device causes a lag of three-tenths of a second in the recording of normal dashes of 4 seconds, though this is practically without importance seeing that, as pointed out in my copending application, the dash may be conveniently comprised anywhere between 3 and 5 seconds.- In order to simplify the disposition of the assembly controlling the length of spaces and the electromagnets 57 60 and 59 provided for that purpose in the above. referred to U. S. application may be replaced 'by a time-lag relay closing its contact after two seconds of energization. This time-lag relay consists, for instance, of a wire FI mounted between'the contact 5 and the contact 22 of relay 42 as disclosed in my said copending application. The said wire will then be traversed by the current during the intervals of time between the 'si nals .andwill lengthen it. This wire contra a contact CT in such a way that this contact is closed when the wire is hot and open when the wire is cold. 9 i

is cheaper to make and simpler than the balance device, and it insures suificient precision for the purpose in question.

The hot-wire time-lag relay could evidently be replacedby any other type of retarded relay such as the dash dot and similar kind.

Suppose that a signal impulse of four seconds has been received through coils 56.

' Since the length of the signal is above the critical length determined by the retarded relay MN the circuit of relay 54 will be completed and attracts its keeper 1. The latter liberates shoulder 2 of the rod 3 which holds the spring the balance wheel 49 in tension with a result that the balance wheel is thus released and startsto swing freely.

The arm of the keeper 1 at the end of its stroke closes the uppercontact of switch 5 with a result that all the points marked +a become of positive polarity, including the contact 6. The latter, however, has been opened because thebalance has started to os-.

cillate. The dash controller assembly is now prepared and ready to measure the first dash. Presupposing that balance wheel 49 makes a complete swing in one second, then during the first half of the second which will be. one half the oscillation of wheel 49 rods 3 and 4 ascend, while during the second half of the second rod 3 descends and closes contact 6. The result of this is that an impulse is sent through the line 51. These movements are reproduced each second and at the end as soon as the impulses stop, contact 6 is open,

27 no longer is short-circuited, it is energized through +a of contact 5, +a of contact 8, 8, 27, to 26 and causes connection of the line 51 with line 52 by way of its contact 9, while it becomes isolated from said line 51 by its con tact 7. However, it will be seen from the last traced circuit thatrelay 26 will remain energized so that contact 8 will remain closed even though contact 7 is broken.

It will be seen that 26 operates at the end of the first second when an impulseis passed, and that 27 becomes operative immediately after this impulse.

Line 51 is then united by way of contact 9 and line 52 to the input end of 28. The latter operates at the end of the second second at the time the second impulse is passed. As the arrangement of 28, 29 is the same as that as of 26, 27 the relay 29 will become operative immediately after the second impulse and thus causes connection of line 51 with group 30, 31 by way of its contact 10.

At the end of the third second at the time of sending out the third impulse, relay 30 will operate; after this impulse relay 31 is energized and causes connection of line 51 over to the group 32, 33.

At the end of the fourth second 32 operates at the instant of the fourth impulse and 33 is energized immediately after this impulse. It will thus be seen that the electromagnets 26, 28, 30 and 32 are successively closed 1 in proportion as impulses are set into the line 51, that is to say, at the end of each second. Since it has been supposed that a four second dash is received at the end of the third second relay 30 when energized has caused current to flow into the line 47, the latter controls the group of recorder electromagnets 42, 43 and 41, 39, the electric operation ofwhich is exactly the same as that described for the set of electromagnets 26, 32, 27 and 33 etc.

Consequently as soon as 30 functions electromagnet 42 is energized through the plus terminal of the right hand contact operated upon by relay 30, line 27, contact 13, relay 42 to minus via contact 36, and is so kept by its contact 12', while relay 41 remains shortcircuited by its keeper 13 and contact 14 of relay 3().

After the four second dash, switch 55 is opened, electromagnet 54 is no longer energized, keeper 1 is released whereupon being drawn downwards by its spring 53 the balance wheel 49 is locked. Now at the same time, contact 5 leaves its upper contact, points +11 are no "longer fed and the release 26 to 32 and 27 to 33 being de-energized assume their original sets.

At this instant the contact 14 of electromagnet 30 is open, the relay 41 is no longer short-circuited, it operates and switches the line 47 by way of contact 11 onto the group r 43-40 through 46. It will thus be seen ice that the reception of the first dash of four I seconds has .resulted in the energization of the recorder group 4246.

Supposing then that a correct series of dashes of the proper length of time is. received then upon the second dash the group of dash relays 26, 32, 27, 33 will again become operative. When 30 is energized a current will be caused to flow in line 47 and the electromagnet 43 will be energized. After the second dash the group of dash relays will come to rest by the recorder relays 42, 43, 41 and 40 will be energized. Upon the third dash thedash relays are operated again, the

line 47 will-operate.

After the third dash the group of dash relays comes to rest, but all the recording relays will then be energized. It will be noted in particular that relay 39 will then be excited 25 lay. 48, the latter closes I '45 64 may become whereupon its contact 16 will be closed thus ringing the bell 65. Relay 39 has a guard coil 38 fed by way of contact 15, the result is that whatever signals may follow the alarm bell 65'will continue to ring until it is stopped. If one of the incoming dashes lasts for five seconds, after the fourth second the relay 33 will operate whereupon its contact 17 connects line 51 with line 34. The result of this is that at the termination of the fifth second when impulsed the relay 35 will become operative and break the common return of the recording relays through contact 36. This group is thus set at rest, in fact another complete correct signal will be required in order to operate the bell 65. In case the dash lasts longer than five seconds relay 35 will operate at each second unless finally the balance 49 is stopped by its damping means 1.'

20 Assuming now that any number at all of dashes has had a duration longer than 1 second. but less than 3 seconds. At the end of the first second 26 has become energized, contact 18 is closed and this feeds the coil 20 of reits contact 19 whereby line '64 is connected with line 34; at the end of the unduly short dash 54 becomes deenergized, contact is moved over to its lower contactand a current is caused to flow in line 64 and consequently line 34, the zero restoring relay contact 35- -36 operates and renders the recorder group inoperative.

But if on the other hand the dash has been correct then upon operation of relay 30, coil 21 of relay 48 would have been energized, the

coils 20 and 21 of device 48 are equal but opposite, their action is neutralized and as a consequence contact 19" would have been opened and the flow of current in. line 64 40 would have been ineifective.

or back contact and a current starts to flow through FI. This wire will then be lengthened. Thus it will be seen that contact CT is closed when the wire F1 is hot and open when it is cold. This time lag relay arrangement is so constructed that it will take 2 seconds to become active. Therefore, at the end of two seconds relay becomes energized with the result that zeroizing relay 35 is affected and the whole system returned to. its ori inal condition.

laim: In a selective apparatus responsive to a certain predetermined series of signal impulses separated by intervals, means for measuring the length of a particular signal impulse comprising a signal responsive device, an oscillating mechanism adapted to be set in motion thereby upon the receipt of a signal impulse and brought to rest at the end of said impulse, an electric circuit, means including said oscillating mechanism for pcriodically sending a current impulse through said circuit and a series of relay devices operativel associated with said circuit and means or successively operating said relay devices in accordance with said impulses, and means comprising a slow acting relay connected between the signal responsive device and said oscillating mechanism for rendering said oscillating mechanism operative only upon receipt of signals exceeding a predetermined length.

. LOUIS LUCIEN EUGENE CHAUVEAU.

It will be noted tliat the relay 48 has a I slight time lag 67 in order that relay 48 may remain energized a short instant after 26 has come to rest. Thus, the zero impulse by line effective. It is evident from what has preceded that every dash lasting longer than a second and less than 3 seconds w causes the system to be restored to zero. Every dash having system because oi: the balance wheel 49 and. b the present. improvement, namely, relay N every dash having a length less than a value predetermined by the relay MN will be communicated to the balance wheel at all.

Check-up on the silence or space periods is effected in the following manner; As long as the signal has not been started it is unnecessary to measure-these periods and it is for this reason that the circuit of wire F1 passes by way-of line 37 and contact 22 of relay 42. Under these conditions immediately after'reception of the first correct dash contact '5 is caused to move to its rest a length less than 1 sec- 7 0nd is unable to produce an action upon th6' retardation of CERTlFlCATE 0F CORRECTION.

Patent No. 1,867,209. u July '12, 1932.

LOUIS LUCIEN UGENE CHAUVEAU.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, line 7, before "Suppose" insert the words "Referring to the drawings the operation of the assembly is as follows"; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office Signed and sealed this 17th day of January, A. D. 1933.

(Seal) I Acting ,Comt nis ioiiie i gi Patents. 

